Clutch Sizes, Fledging Success, and Nest-site Characteristics of Sharp-shinned Hawks in Kentucky.

Because Sharp-shinned Hawks (Accipiter striatus) are among the most secretive of North America's forest-breeding raptors, little is known about their breeding biology, including the characteristics of their nesting habitat. In 2009 and 2010, we searched forest stands in Kentucky and located 11 nests, all in pines (Pinus spp.). Nests were at a mean height of 18.6 ± 1.4 m in trees with a mean height of 23.7 m. Comparison of the characteristics of nest sites and randomly selected unused sites revealed significant differences (P = 0.021). Discriminant analysis revealed that six variables (foliage cover, mean tree height, basal area, percent deciduous canopy cover, distance from edge, and distance from road) permitted the best discrimination between used and random sites. Sharp-shinned Hawks nested in areas closer to edges and in areas with denser stands of taller conifers and denser understory. All nests were in stands of young (~25-50 years), even-aged conifers about 18-25 m in height. Nest sites were also closer to edges where stands of dense pines transitioned into areas with more, shorter deciduous trees and less foliage cover than nest sites. These adjacent areas may provide better foraging habitat for nesting Sharp-shinned Hawks because small birds, their primary prey, are more abundant in mixed stands than in dense stands of conifers where they nested [ABSTRACT FROM AUTHOR]